hi guys,
solve cos2x - 3cosx +2 = 0 for 0 < x < 360
which formula should I use? is it the sum to product? I dont really know how to go about doing it! some advice pls!
thanks!
No, you've missed out your 3cos(x) term.
FYI has no real solutions. This is because for all real x. Adding 1 will always result in a positive answer where x is real
The original question is
What Grandad said is to change - the 3cos(x) term is unaffacted.
I have used square brackets to show this more effectively
You can simplify the constant terms to get it into the form :
You can the solve the quadratic using your favourite method although this one factorises.